On 17/11/09 17:31, Chris Boyd wrote: >> I've seen vibration impact disk i/o on sata disks as well. > There's another WD disk in the box on a different controller that does not suffer from the problem. Are they identical ? swap them around in the chasis and see if that makes any difference. I had a 4 disk raid10 built on samsung fd2 1.5TiB disks, getting ~ 123 to 128MiB/sec. Moving them from the ich5 machine to a fanless Via Esther ( 1200Mhz ) based box took me upto 240MiB/sec and its the CPU here that cant go faster. Same rig/kit/rack point/psu - just a diff mobo with all the fans from around the mobo removed. Just the ones in the psu churn enough air to keep the disk <= 36 Deg C. - KB